Production of moulds for metal casting



Sept. 22, 1959 M. P. A. PINCHON 2,904,858 I PR LDS FOR METAL CASTINGFiled April 8, 1957 2 Sheets-Sheet 1 FIG.

BY I

Maul S. MM

Sept. 22, 1959 AQPINCHQN 2,904,858

PRODUCTION OF MOULDS FOR METAL CASTING Filed April 8, 1957 2Sheets-Sheet 2 Wino. s. 5M0.

United States Patent PRODUCTION DF'MOULDSFOR IVIETAL CASTING MichelPhilippe Auguste P inc hon, Hautmont, France, .assignor to Soc'itAnonyme Fonderies Chokier, Nerd, "France, a com an of France Applicati0nApril 8, 1957, Serial No. 651,316 Claims priorit application FranceApril 13, 1956 7 Claims. '01. -22-'20) I This invention relates to aprocess and an apparatus for the series'producti'on of sand mouldsfor'rnetal cast- In the process according to the present invention, thesand is pressed on a pattern plate inside a moulding box carried by'amanipulating arm, the arm being adapted to pivot about a vertical axis.The compacted box is then carried by the arm from the place where thebox was filled to a conveyor on to which it is lowered. The "conveyormoving in intermittent steps carries the mould to an appropriateposition for casting.

The objects of the invention are twofold.

Qne object is to provide a process in which'the metal can be cast intothe sandmould after it has been'removed from the moulding box in whichit was rammed. In such a case the moulding box can be connected rigidlyto the manipulating arm or may be such that it can only be disconnectedfrom it with difficulty. The moulding box is separated from the mouldproper by vertically displacing the box while holding the mould on theconveyor by means of a press. The conveyor carries the mould thus formedto the casting position. It is sometimes desir able to support the mouldin an auxiliary box during the actual casting.

A further object of the invention is to provide an in stallation orcarrying into effect the process. Such an installation comprisesessentially at least one moulding pressforpressing the sand onto apattern within a moulding box, atleast one substantially horizontalmanipulating arm carrying the box at one 'end and which is mounted atthe other end on a vertically telescopic pivot and is adapted to rotateabout a vertical axis through the pivot and a conveyor adapted toreceive the mould from the manipulating arm and to carry it step by stepto the casting position.

A still further object is to provide apparatus for removing the sandmould proper from the moulding box, when the box is not to be separatedfrom the manipulating arm. The installation then also comprises astripping press, situated above the place Where the manipulating armdeposits the mould on the conveyor. The press holds the mould proper onthe conveyor and the manipulating arm --moves'vertica'lly carrying themoulding box with it.

A further object is to provide a convenient means for supporting thesand mould during casting after'it has been removed from its originalmoulding box. It com- =prises carrying the mould on the conveyor belowan endless chain having depending from it auxiliary boxes. The belt 'isarranged so that the boxes have a descending run for the purpose ofgradually covering each mould with a box while it is being transportedalong the conv'eyor, a horizontal run, whose length is determined by thespeed of the conveyor and on the time required for the operations ofcasting and cooling the metal, an 'as- (Sending run for progressivelyseparating the mould containing the castrn'e'tal from the auxiliary box,and a return runwhich is offset relatively to the three preceding2,904,858 Patented Sept. 22, 1959 runs and'connects the ascending run tothe descending run.

An example of an installation according t o the invention will now bedescribed with reference to the accompanying drawings in which: I v I Iv Figure l is a perspective View of part of an installation.

Figure 2 is a side view of the said installation taken parallel to theaxis of the conveyor.

Figure 3 is a sectional View of the moulding press. I, Figures 4 is asectional view of the manipulating of the installation and the pivot ofthe said arm.

The installation illustrated is composed of t w om'o u lding presses,tWo manipulating arms, a block-removing press, a conveyor, an endlesschain carrying "the auxiliary boxes, and'acasting apparatus which is notshown.

Each moulding press comprises a frame '1, a support 2for a patternplate, a pressure head 3 fixed to the upper part of the frame above thepatter-n plate, a sand reser: voir 4 arranged rearwardly of the patternplate, a'slide 5 with sand supply control device ",6 and closure members7 mounted on the slideways at the level of the lower portion of the sandreservoir. Slide 5 is horizontally reciprocable by means of hydraulicactuator '5.

Each manipulating arm is composedof an arm 9 which ispivotable through180 about a pivot it and a moulding box 8 is fixed to and forms anintegral part of each arm 9. The pivot itself is moved in upward anddownward direction by a jack 10h.

The manipulating arm of the lower part of the mouldingbox also allowsthe box to be turned upside down. Preferably thehoriz ontal rotationalmovement of the arm is divided into two movements of 90 each so that themould may be inspected after compression and before being deposited onthe conveyor. The horizontal rotation of the arm is effected by atooth'ed sector 11 'fixedto the base of said pivot which is driven by arack 12 eontrolled by jack 13. The division of the horizontal rotationalmovement of the lower arm about the pivot into two movements of 90 isbrought about by means of two jacks 13 each controlling a rotation of90, or by a. single special jack which operates in two stages.'

, The turning of the box of the lower block is eifected by a toothedsector 14 fixed to the end of the manipultitihgarm shaft. As is shown inFig. 4, the arm 9 extends transversely through the cylinder 10 and issupported for turning movement about its longitudinal axis b ysuit'abl'e bearings carried by the cylinder 10. The toothed sector 14 isfixed to the left end of the arm '9, as viewed in Fig. 4, and mesheswith a vertical rack one end of which is connected with the piston of ahydraulic jack supported at the side of the cylinder 10 andcornmunicating with any suitable source of fluid under pressure formoving the latter rack up and down so as to turn the arm 9 about itsaxis for inverting the lower or drag mold box 8. The top end of the rackwhich cooperates with the sector 14 is guided for axial movement by asuitable bearing fixedly carried by the cylinder 10 and shown at the topof Fig. 4.

Each box has at its end and on each side a roller 15 which serves toguide the descent onto the pattern plate and to guide the placing of themould on the conveyor.

The block removing press or stripping press is a hydraulic jack situatedabove the conveyor in the axis of alignment of the two moulding boxeswhen they are brought together over the conveyor. The piston rod of thisjack comprises at its lower portion a plate whose external dimensionsare slightly less than the smallest internal dimensions of the boxes.

The. object of the stripping press is to hold the two blocks on theconveyor while the boxes are moved upwards and separated by themanipulating arms. The

pressure should be sufficient to detach the sand from the walls of theboxes but should not be so great as to risk crushing the mould.

The conveyor 17 is of a continuous rectilinear type having a planesurface. It advances intermittently, syn chronised with the movements ofthe pivoting arms. Each forward step is equal to about 1 /2 times thelength of the blocks and takes place whilst the boxes are engaged in thepresses.

The conveyor must be of such length as to perm1t casting in the blocksafter they have been moulded, and a sufficiently long cooling time. Thelength therefore depends on the nature of the parts and the time whichthe machine takes to carry out a complete moulding cycle.

An endless chain 20 carries auxiliary boxes 21 which are spaced apartfrom one another in the horizontal sense by a distance equal to one stepof the conveyor 17. The chain 20 travels over rollers 22. Its path oftravel is in four separate parts and comprises a descending run 200 inwhich the auxiliary boxes move downwardly to surround the mould, ahorizontal run 2% in which time the casting is effected and the metalcooled, an ascending run 200. in which the auxiliary boxes 21 areremoved from the moulds and a return run 20a connecting the runs 20d and29c. The return run is offset relatively to the plane of the conveyor 17so as to return the auxiliary boxes 21 after they have been separatedfrom moulds to the beginning of the run 20c.

An example of the method for making a two part mould is as follows:

The slides are displaced from their normal positions by the hydraulicactuators 5 so that control devices 6 move from their normal positionbeneath reservoir 4 to above the boxes 8. The closure members 7 areopened by the hydraulic actuators 7' which are mounted in the slides 5so that the sand in the devices 6 fills the boxes 8 covering the patternplates 2. The pistons 3 are moved downwards, while the devices 6 arestill in position to compress the sand into the boxes 8 and on thepattern plates 2. The pistons 3 are then raised and the slides 5 aremoved rearwardly. In this movement, the supply control devices 6 returnto below the reservoir 4, are closed by the closure member 7 and arere-filled with sand. This displacement of the supply control devices 6causes the upper part of the box 8 to be scraped. At the same time thepivot 10, which carries the manipulating arm carrying the box 8, islifted, the latter carrying away the sand which it contains, whose lowerface reproduces the shape of the pattern plate 2.

The pivot 10 of the box 8 of the upper part of the mould is pivotedthrough 180 about its vertical axis to move the box to a position abovethe conveyor 17. Similarly when the moulding box 8 containing the lowerpart of the mould is packed it is also rotated through a 180 path by therotation of the pivot 19.

If it is required to place cores in the mould, the rotational movementof 180 on the part of the pivot may be broken down into two rotationalmovements of 90 each. The movement of the pivot 10 may be interruptedbetween the two rotational movements in order to permit the cores to beplaced in position.

The two boxes 8, one corresponding to the lower part of the mould andthe other to the upper part of the mould are thus positioned one abovethe other above the conveyor 17 and below the stripping press piston 16.

A downward movement is imparted to the pivots 10 so as to place the twoblocks simultaneously on the stationary conveyor 17. At the same timethe stripping press piston also moves downwardly.

The pivots 10 are raised simultaneously, while the piston 16 remainsstationary. The boxes 8 separate from the moulds which they containleaving the moulds on the still stationary conveyor 17. The blockremoving piston 16 then returns to its retracted position.

The pivots 10 with their boxes 8 travel again to above the patternplates 2, executing the same movements as previously, but in the reversesense, and the operations described hereinbefore are repeated.

During the return movement of the pivots 10 to above the pattern plates2, the conveyor 17 moves by one step.

The blocks which have been assembled on the conveyor move below anendless chain 20 from which are suspended auxiliary boxes 21. Thisendless chain moves step by step each step being equal to an advancingstep of the conveyor 17. The endless chain 20 passes over the rollers22, in such manner that the upper run 20a of the endless chain 26 is ina diiferent plane from that in which the conveyor 17 is situated, whilstthe runs 20c, 2% and 20d are situated in the plane of the conveyor. Theruns 20c and 20d are inclined, whilst the run 20b is horizontal.Auxiliary boxes 21 corresponding to the run 200 descend to coverprogressively the assembled moulds. During the run 29b the auxiliaryboxes 21 support the moulds without moving relatively thereto but duringthe run 20d they detach themselves progressively from the moulds.

During the travel of the moulds, corresponding to the run 20b, the metalis cast into them and allowed to cool. Thus the auxiliary boxes 21 holdthe two sand moulds in position despite the pressure of the metal. Inorder to bring about this result, the auxiliary boxes 21 should be of anadequate weight and strength.

When the auxiliary boxes 21 have been removed from the moulds the boxesreturn along the run 20a to the starting point, whilst the sand mouldscontinue to be carried along by the conveyor 17. The moulds are brokenup and the cast metal removed therefrom.

In the drawings, the conveyor 17 which is illustrated is a straightconveyor. In fact the conveyor will advantageously follow a closed loopcourse.

I claim:

1. In a casting apparatus, in combination, mold-forming means for makinga sand mold part in a mold box located at a predetermined position onsaid mold-forming means; an arm; a mold box fixedly connected with saidarm for movement therewith; conveyor means; moving means operativelyconnected with said arm for moving the same between a first locationwhere said mold box fixed thereto is in said predetermined position onsaid mold-forming means to have a mold part formed therein by saidmold-forming means; and a second location where said box fixed to saidarm is located with the finished mold part therein over said conveyormeans; and means located on said conveyor means for stripping the moldpart from the box so that the mold part is conveyed by the conveyormeans without the box which is fixed to said arm.

2. In a casting apparauts as recited in claim 1, said conveyor meansbeing adapted to transport a series of sand molds without the boxes inwhich they were prepared, said apparatus further including secondconveyor means located at least in part over said first mentionedconveyor means and operating in synchronism therewith; and a pluralityof reinforcing boxes for reinforcing said molds on said first-mentionedconveyor means carried by said second conveyor means and moved therebyfirst downwardly around said molds on said first conveyor means,respectively, then together with said molds along the path through whichthey are moved by said first conveyor means, and finally upwardly awayfrom the molds, so that said reinforcing boxes will reinforce the moldsagainst the forces of casting material therein while the molds aretransported by said first conveyor means.

3. In a casting apparatus, in combination, elongated substantiallyhorizontal conveyor means; a pair of moldpreparing means forrespectively preparing upper and lower sand mold parts respectivelylocated at opposite sides of said conveyor means; a pair of carriersrespectively located at opposite sides of said conveyor means betweenthe latter and said pair of mold-preparing means; moving means connectedoperatively with each carrier for moving the same upwardly anddownwardly along a vertical axis and for turning the same around saidaxis; a pair of substantially horizontal arms respectively carried bysaid pair of carriers and a pair of upper and lower mold boxesrespectively fixed to said arms for movement at all times therewith,said moving means actuating said carriers to locate said boxes firstrespectively at said pair of mold-preparing means, to have upper andlower mold parts respectively formed therein, and then one above theother over said conveyor means to locate the upper mold part over thelower mold part on said conveyor means; and means located over saidconveyor means for holding the mold parts thereon while said movingmeans moves said arms and boxes therewith upwardly away from the moldparts to strip the boxes therefrom so that the conveyor means thenconveys the mold without the boxes in which it was formed.

4. In a casting apparatus, in combination, elongated substantiallyhorizontal conveyor means; a pair of moldpreparing means forrespectively preparing upper and lower sand mold parts respectivelylocated at opposite sides of said conveyor means; a pair of carriersrespectively located at opposite sides of said conveyor means betweenthe latter and said pair of mold-preparing means; moving means connectedoperatively with each carrier for moving the same upwardly anddownwardly along a vertical axis and for turning the same around saidaxis; a pair of substantially horizontal arms respectively carried bysaid pair of carriers and a pair of upper and lower mold boxesrespectively fixed to said arms for movement at all times therewith,said moving means actuating said carriers to locate said boxes firstrespectively at said pair of mold-preparing means, to have upper andlower mold parts respectively formed therein, and then one above theother over said conveyor means to locate the upper mold part over thelower mold part on said conveyor means; means located over said conveyormeans for holding the mold parts thereon while said moving means movessaid arms and boxes therewith upwardly away from the mold parts to stripthe boxes therefrom so that the conveyor means then conveys the moldwith out the boxes in which it was formed; and reinforcing meanscooperating with said conveyor means for reinforcing the mold thereonwhile casting material is located therein.

5. In an apparatus as recited in claim 3, each of said mold-preparingmeans including a stationary pattern table on which each mold part isformed in its box, and a compacting ram located over said table forcompacting the sand in the box on the table.

6. In an apparatus as recited in claim 3, said means located over saidconveyor means for holding the sand mold parts thereon being carried bya support which extends between and is carried by said pair ofmold-forming means.

7. In an apparatus as recited in claim 5, each of said mold-preparingmeans further including sand storage means, and transfer means fortransferring a measured amount of sand from said storage means to saidbox.

References Cited in the file of this patent UNITED STATES PATENTS1,119,680 Brown Dec. 1, 1914 1,134,398 McCarte Apr. 6, 1915 1,752,175Harmes Mar. 25, 1930 1,877,494 Bullock Sept. 13, 1932 2,325,501 GedrisJuly 27, 1943 2,575,123 Pollard et a1 Nov. 13, 1951 2,792,603 AndersonMay 21, 1957 FOREIGN PATENTS 470,863 Germany Feb. 1, 1929 678,070 GreatBritain Aug. 27, 1952

